a) Field of the Invention
The invention is directed to a screw-on hinge for a door or flap which is arranged so as to be swivelable vertically or horizontally at a frame or wall, wherein the door or flap is held in releasable manner in at least one swivel angle position, this screw-on hinge comprising a first hinge part which can be fastened, for example, to the frame, and a second hinge part which can be fastened, for example, to the door or flap, each of which hinge parts is symmetric with respect to its center bisecting line and comprises a bore hole for receiving a hinge pin arrangement, wherein the hinge pin arrangement comprises a sleeve which is connected with one hinge part so as to be fixed with respect to rotation, and a springing catch device is arranged between the sleeve and the other hinge part.
b) Description of the Related Art
A screw-on hinge of the type mentioned above is described in U.S. Pat. No. 5,412,842. The known hinge makes it possible to hold a door in releasable manner at a predetermined position relative to the frame when the door is swiveled for the purpose of opening or closing. In the known arrangement, the sleeve is provided with recessed radial bore holes into which spring-loaded balls can run. When the balls run in, the sleeve and therefore the hinge part (hinge tabs) connected with this sleeve and therefore also the door are held in the corresponding position with a force which depends on the spring tension and run-up angle of the balls. Bore hole spaces which are oriented radial to the hinge axis are provided in one hinge part for receiving the spring. These bore hole spaces are open at one end toward the sleeve and receive the balls, while the other end of the bore hole can be closed by a slide at which the pressure spring is supported. This is disadvantageous in that it requires a special construction of the at least one hinge part (hinge tab); this special construction leads to an increase in the structural height of the hinge part. There are also relatively many structural component parts. In the embodiment form shown in the reference, there is a total of three balls, three pressure springs and an insertable holding plate which are necessary for achieving the desired result. Difficulties also arise with respect to assembly because the balls, pressure springs and plate cannot be mounted until the sleeve-shaped hinge pin which is provided with the run-in openings for the balls is in place within the two hinge parts. A further disadvantage with balls is the punctiform pressure point which leads to high area pressure and rapid material wear.
DE 29 41 860 A1 discloses a hinge comprising two hinge parts in which the hinge pin is formed by a sleeve in which is arranged a pressure spring which presses the end of the sleeve against an insert in order to achieve an elastic locking at certain rotational angles, wherein the end of the sleeve is provided with projections, the sleeve is connected with one hinge part so as to be rigid with respect to rotation and the insert is arranged in the other hinge part and is provided with radial notches. It is disadvantageous that the two hinge parts can not be fixed axially relative to one another and that the hinge can therefore be used only in connection with a second hinge of the same type that is constructed in the opposite sense (page 6, lines 16-21).
DE 24 18 147 discloses a hinge for a motor vehicle door with two hinge parts which are centered by a hinge pin and carry cooperating fitting surfaces. The fitting surfaces which are outfitted with notches and projections are pressed onto one another by the weight of the door or by springs (page 2, line 14), not described more fully, for fastening in an open position. One hinge part encloses the other in a fork-like manner.
DE 23 42 945 likewise describes a hinge for a motor vehicle door having a locking device. By means of a helical pressure spring 10 which can be reinforced by a second, coaxially arranged pressure spring 9, control plates which are provided with radial recesses and connected with one hinge part 3 so as to be rigid with respect to rotation are pressed against pins 11, 12 which are guided transversely through the hinge bolts 6 which are connected with the other hinge part 1 so as to be rigid with respect to rotation.
The hinge in EP 0 266 490 B1 (see FIG. 4) which is provided for a lockable vehicle door has two plate spring assemblies which are directed opposite to one another and held by a screw.
DE-OS 22 35 555 discloses hinge straps for a hinge with locking arrangement having (plate) springs which are disposed coaxially and arranged on the hinge pin (claim 2).
DE 31 26 933 A1 relates to a hinge strap for doors in which locking positions are possible. A holding force is caused by residual closing pressure (page 7, line 11).
DE 36 24 649 A1 mentions an upset bolt 4 and accordingly discloses the rivet principle for a fixable hinge for motor vehicles.
DE 39 05 351 A1 shows a folding door and also hinges with a catch device, wherein, according to column 2, lines 49-51, hinge parts and catch parts can also be injection molded from plastic and it is also possible for a bearing pin made of metal to be injection molded in plastic.
DE 196 19 473 A1 mentions a plastic slide in connection with a removable door hinge with a structurally combined door lock.
Most of the hinges known from the references mentioned above lack compactness, the spring devices are often also visible and not only have an unattractive appearance but also collect dust. Apart from U.S. Pat. No. 5,412,842 (and possibly DE 29 41 860 A1) which was mentioned above as the prior art coming closest, none of the references describes a hinge that is suitable for sheet metal cabinet doors.
It is the primary object of the invention to avoid the above-mentioned disadvantages and to provide a screw-on hinge according to the type mentioned in the beginning which has a simpler construction, a more compact outer shape, fewer individual parts, is extensively symmetric and can therefore be mounted more easily and has a longer life.
This object is met in that the hinge pin device comprises two parts and in that one end of one hinge part which faces the other hinge part forms the catch device, and in that the catch device is formed by an end face of the sleeve and comprises a helical pressure spring arranged axially inside the sleeve.
This feature makes it possible to utilize the space of the hinge bolt for the catch device and the use of one of the screw-on hinge parts of the screw-on hinge for this purpose, which caused the problems described above, is avoided. In addition, the end face of the sleeve provides a contour surface which makes possible a catch device with relatively low area pressure which reduces material wear and prolongs the life of the hinge.
The symmetry of the hinge and its parts facilitates not only assembly but also subsequent modification of the fitting of the door.
According to a further development of the invention, the catch device comprises a shoulder or pocket hole bottom surface which is formed or arranged at the end of the bore hole for the hinge pin in the hinge part and in which are provided recesses or protuberances corresponding to protuberances or recesses of the end face of the sleeve, wherein the pressure spring presses the sleeve with its protuberances or recesses against the shoulder or bottom surface with its recesses and protuberances (recesses, projections). This is a particularly simple step for achieving the desired catch positions without using balls which can get lost and which, in addition, lead to difficulties when mounting the hinge.
For simplified production, it is advantageous when the non-rotational connection between one hinge part and the hinge pin is achieved by means of a tongue-in-groove arrangement or, alternately, by a non-circular cross-sectional shape, e.g., a prismatic shape, of the cross section of the hinge pin on one hand and of the bore hole in the hinge part in which this hinge pin is to be inserted on the other hand.
When the hinge pin has the shape of a sleeve, this is advantageous not only for economizing on material but also for facilitating the production of projections and recesses at the end face of this sleeve-shaped hinge pin. Moreover, there are special advantages to other embodiment forms to be described below such as the possibility of accommodating a helical pressure spring and screw bolt or rivet.
A hinge shape which is especially stable and simple at the same time is one in which one hinge part encloses the other hinge part in the manner of a fork as is also seen in the prior art. Particularly with this shape of hinge it is advantageous that the sleeve-shaped hinge pin is constructed in two parts and that the one end of one hinge pin part, which end faces the other hinge pin part, carries a catch device. In order to increase the locking force it is advantageous, according to another embodiment form of the invention, when catch projections or catch recesses are provided on the end faces of both hinge pin parts of the two-part hinge pin in a corresponding manner, which catch projections or catch recesses engage in corresponding recesses and projections formed by annular shoulders in the hinge part bore hole in which the corresponding ends of the hinge pin parts are received.
The other end of the hinge pin parts can then be received in the hinge pin bore hole of the other hinge part so as to be rigid with respect to rotation but possibly so as to slide in axial direction. Because it is held in a sliding manner, it is ensured that it can deflect in axial direction when locking or unlocking.
The spring arrangement for the catch device is also advantageously constructed in two parts; in particular, the ends of the spring facing away from each other can be held by a screw penetrating the spring parts, wherein one spring could be supported on the head of the screw and the other spring could be supported on a nut which is screwed onto the screw. This has the great advantage that the force with which the catch devices exert the holding force need not be absorbed by parts of the hinge so that these hinge parts are additionally loaded, but can be applied by the screws which do not otherwise exercise any holding function. This step greatly reinforces the stability of the entire arrangement. At the same time, the two fork prongs of the fork-shaped hinge part are relieved of bending forces.
It has proven advantageous when the end face of the sleeve has four projections (or raised portions) or recesses having a distance of 90 angular degrees from one another. This results in particularly favorable ratios for hinges enabling an opening angle of 180xc2x0. This arrangement enables a function in which there is locking in the closed position, in the position which is opened by 180xc2x0 and at half of the opening angle at 90xc2x0. Further, this is a good compromise between the quantity of catch projections and the width of the projections, which leads to a good compromise between stability and holding force.
In this case, there should also be four recesses or projections formed by the shoulder and they should have a spacing of 90 angular degrees. Matching these projections and recesses to one another results in a particularly stable hinge shape and in a particularly high holding force in the different catch positions.
It is usually advantageous that the catch positions are oriented in such a way that a catch position is achieved just as the closing position of the door or flap is reached. Alternatively, however, the catch device can also be constructed in such a way that the spring pressure of the helical spring within a small angle of rotation extending around the catch point leads to a torque in the direction of the catch point and that the orientation of one catch point for the closing position is carried out in such a way that the catch point is not yet entirely reached when the door or flap is closed and, therefore, there is a torque acting in the closing direction. As a result of this, the door is held in its closing position with a certain pressure so that there is no flapping motion or play, as could happen when the door is in the closing position exactly at the zero point of the catch position.
Usually it is advantageous when the hinge parts are constructed in such a way that they can be screwed onto mutually flush fastening surfaces of the frame on one side and door or flap on the other side.